Travel controller and method for travel control

A travel controller comprising a processor configured to:

• perform driving control of a vehicle at an autonomous driving level that is a first autonomous driving level in which a driver of the vehicle is not obligated to watch or a second autonomous driving level in which the driver is obligated to watch;
• notify, for a predetermined period, the driver of a request for driving the vehicle or taking a driving posture allowing for the driving, when the autonomous driving level of the driving control changes from the first autonomous driving level to the second autonomous driving level;
• determine an attention level of the driver, based on an output of a sensor provided for the vehicle, the attention level being a level of attention to driving;
• and
• modify the predetermined period so as to be shorter by keeping a start time of the predetermined period unchanged and modifying an end time of the predetermined time period to be earlier, when the determined attention level is high than when the determined attention level is low.